Adjustable dial



United ,t StatesPatent O 3 claims. ,.(cl. 1924-8) The fp res-ent invention relates to an improved adjustable dial indicato; mechanismV and nmore particularly to an improved adjustable micrometer dial adapted for association with the feed mechanism of a movable machine element.

The dial mechanism referred to comprises generally `avdial which isadjustably mounted on a movable part of the feed-mechanism and is graduated to indicate accurately the extentby which the `machine element is moved.

It isA a principal object ofthe invention to provide a` dial mechanism which `is well adapted for nger control by the operator forelecting a ready adjustment in the positionV of the dial to an exactly determined position, and for thereafter positively locking the dial in the adjusted position. i

lIn carrying out the invention applicants `provide a rotatable dial mechanism which isassociated withthe feed' mechanism of a movable machine element as, for

example, the table of a milling machine.V The dial is connected with thefeed mechanism through a double acting wedge type clutch whichnormally operates to lock the dial in a lix'ed position `with respect to the driving clutch element.` The dal'mechanis'm includes a manual- J ly yoperable releasingf'ring which is readily adapted for linger adjustment by` the operator, first, to'release `the clutch, andv thereafter to turn the dial to a desired posi` tion of adjustment which can be intermediate the graduations `onithe `dial permitting an infinite degree of accuracy inthe setting. The releasing ring is then'released by the operator so thatthe double acting wedge clutch becomes operative to lock` the dial in the adjusted position. f

- With `the above and other-objects in view as may hereinafter appear, the several features of the invention conf `sist also i'n the devices, combinations and arrangement of parts hereinafter described'and claimed, which togetheriwith Ithe advantages to be obtained thereby will be readily understood byone skilled in the art from'the following description: taken in connection with the accompanying I Adrawings ,in which,v

Fig. lis a somewhat fragmentary view of a machine tool support includingthe feed screw and certain of the driving connections and the associated manual control, and 'a dial mechanism whereby the manual control dial mechanism;

Fig. 3, is an enlarged detail sectional view of a portion ticularly the preferred form of applicants adjustable micrometerdial mechanism associated therewith. ',Fig. 4 is a somewhat fragmentary view showing particularly the micrometer `dial mechanisml of Fig.` 3 with the releasing ring pushed inward to release the double .I

2,914,153 Patented Nov. 24, 1959 icc ball wedge clutch mechanism by means of which the dial lis normally turned with the driving element of the clutch;

Fig. 5 -is Va sectional view taken on line 5--5 of Fig. 3 to illustrate the double ball clutching mechanism in its locked position;

i Y Fig. 6 is a sectional view similar to Fig. 5, but taken on line 6 6 of Fig. 4 to show the balls forced together into a releasing position.

Fig. -7 is a detail sectional View looking from the side of one of the double ball clutches on line 7-7 of Fig. 5, showing the releasing ring in its retracted position and with the balls of the double Wedge clutch engaged;

Fig. 8 is a detail sectional view looking from the side of one of the ball clutches on line 8-*8 of Fig. 6 showing bevelled anges of the releasing ring in their advanced clutch releasing position corresponding to that position shown in Fig. 6;

Fig. 9 is an exploded view of the dial mechanism shown in Figs. l to 8 inclusive including particularly from left to right the releasing ring, the dial, the cam ring, the spring pressed double ball clutching devices, and the l flanged ball retaining ring; and

o Figs. 10 to 14 inclusive illustrate a modified form of the invention in which the releasing ring is supported for a small rotational movement in either direction in relation to the dial in order to release the double ball clutching mechanism and thereafter to effect the desired .adjustment of the dial in the corresponding direction."

Fig'. l() being a sectional view looking from the side of the adjustable dial mechanism;

Fig. 11 being a detail sectional view taken on line 11--11 of Fig. l0 to illustrate the slot and key connection between the releasingring and the dial supporting Fig. l2 being a sectional view taken on line 12-12 of Fig. 10 showing the'releasing ring lrotated in a clockwise direction to disengage the bouble ball clutching device y and to permit rotation of the dial in the same clockwise direction as shown by the arrow;

Fig. 13 being a detail sectional view looking from the `iside of one of the double ball clutching devices with the control anges of the releasing ring shown in the interthemanual feed mechanism f or a milling machine table.

' Referring particularly to Figs. 1 and 2, the Work table -of a milling machine, which may be of ordinary description, is indicated at 20 having slide surfaces 22 which engage a l cooperating dovetail way on the machine not shown. Feeding movements 'of the table are effected by means of the manual driving connections of the machine tool l support shown generally in Fig. 1 illustrating more parof the usual feed screw 24 which passesthrough a bore formed in a depending bracket 26 on the table and has secured thereto two flanged collars 28 spaced apart for engagement with opposite sides of the depending bracket 26. Power actuation of the table is effected through connections which include a power shaft 30, a gear 32 on thefshaft, and a gear 34 meshing therewith which is carried on clutch sleeve 36 adapted for clutcning engagement with the feed screw 24 through a clutching device not specifically shown.

The manual actuation of the table is effected by means of a hand lever 40 which is operatively connected by meansof a clutch 43 with a hollow table drive shaft 42 which, at the right end, as shown in Figs. l and 3, is prowith a cooperating clutch element 46 forming part of the driving connections to the lead screw 24. When it is desired to advance the table manually to an exactly predetermined position, the operator will shift the hand lever 40 and by means of clutch 43 engage the hand lever to the screw 24 and at the same time disengage clutch 46 from clutch 44 and then positively disconnect `the power drive connections for the table from shaft 30. No further illustration is believed necessary of these connections which are well known and form specifically no part of the present invention.

The last incremental amount by which the table is to be advanced by hand operation may be indicated accurately by `effecting a corresponding setting of the adjustable micrometer dial mechanism indicated generally in Figs. 1 and 2.

The adjustable micrometer dial mechanism provided ,in accordance with the present invention for adjusting and for locking the dial in its adjusted position comprises a double acting wedge type clutch mechanism which is connected between the drive shaft 42 and dial S4, which rotates with relation to a stationary indicator S, and a manually operable releasing ring and adjusting ring 56 which is actuable to release the 'clutch effecting the `required rotative adjustment of the dial 54, and thereafter to engage the clutch and thereby to securely lock the dial in its adjusted position.

Referring particularly to Figs. 4 and 5 the dial 54 is keyed to a sleeve 58 having formed on the end thereof, a `cam ring 60, which is adapted to cooperate with an overlying ange portion 61 of a ball retaining housing 62 which is sleeved upon and keyed to turn with the shaft 42. The cam clutch ring 60 is formed with the three` formed portions 64 against which are engaged pairs of balls 66 and interposed springs 68, which are confined radially of the shaft 42 between the cam ring 60 and ange portion 61 of the ball retaining housing 62. From an inspection of Fig. 3 it Will be noted that the hub portion of the ball retaining housing 62 and the abutting sleeve ring 58 are supported against axial movement on the shaft 42 in one direction by engagement with a flange 72 on the shaft 42 and against movement in the opposite direction by engagement with a retaining stop ring 74 recessed into an annular groove formed in shaft 42.

With this arrangement, as shown for example in Fig. 5 the spring 68 normally forces the two associated balls 66 apart into locking engagement between the flange portion 61 of the housing 62 and the formed surfaces 64 of cam ring 60 so that the shaft 42 and dial 5-4 are secured by the clutch device to turn as a unit.

The releasing ring 56 is mounted on the sleeve hub 58 of the cam clutch ring 60 for a limited axial movement toward and away from the dial 54, and is keyed to turn with the dial assembly including the hub and dial 54 by means of a key 78. The releasing ring is knurled for manual operation and is forced yieldably away from the dial 54 against the retaining ring by means of compression springs 80 as shown in Figs. 3 and 4 seated in recesses in the releasing ring and engaged against the outer face of dial 54. The releasing ring 56 has also formed thereon as best shown in Fig. 9 three accurately formed segmental members 82 which are equally spaced from one another about the face of the releasing ring 56 and which project through slots 84 in the dial 54. Each of the segmental members 82 is formed with two beveled corners 86 which have a camming action when the releasing ring is forced inwardly toward the dial 54 to engage with and move toward one another the balls 66 comprising each of the three double ball clutching units. It will be noted that whereas the clutching action of the balls takes place between the radially spaced cam clutch ring 60 and the outer ange 61 of the ball retaining housing 62, the clutch yreleasing action by means of which the balls 'are moved toward one another is caused by a thrust axially of the adjusting ring 56, at which time the balls are supported against the end 4face of `the ball 'retaining housing 62. It will be readily appreciated that while the releasing ring is held in its inward position by the operator each of the three double ball clutching units is disengaged permitting the dial to be readily adjusted by a manual rotational movement of the releasing ring with relation to the housing 62 and drive shaft 42 to which it is secured. This rotatable movement occurs when segmental members 82 contact end of sl'ots 84. When the releasing ring is released by the operator and is permitted to return to its initial vposition shown `in Fig. 5 under the inuence of springs 80, the double ball clutching elements again become operative to lock 'the dial in exactly the position of adjustment desired.

A modied form of clutch releasing and adjusting means for the dial lis particularly shown in Figs. 10 to 14 inclusive. In this form of the device the releasing ring designated at is keyed to sleeve hub 58 of cam clutch ring 60 by .the engagement of key 92 in a relatively wide slot 94 inthe hub of the releasing ring 90 (see Fig. 11), so that a limited rotational movement of the releasing ring with relation to the cam clutch ring 60 and dial 54 is permitted. The releasing ring 60, in this form of the Adevice is ixedly supported between the ball retaining housing 62 and retaining ring 74 against axial movement. The releasing ring 90 is also provided with three segmental members 96, which in this case as best shown in Figs. 13 and 14 are rectangular in shape, and extend through the slots 84 in the dial 54 to a point closely adjacent the end wall of the ball retaining housing 62. The limited Vrotational movement permitted to the releasing ring 90 and segmental members 96 passing through the slots in the dial 54 is suflicient to cause the said members 96, when turned in one or the other direction, to engage with the adjacent balls 66 of the double clutch assembly, thus releasing the dial from clutching engagement with the housing 62 and permitting adjustment thereof in the direction of rotation Aof the releasing ring 90. When the desired position of adjustment is reached, the releasing ring 90 is released by the operator, thus permitting the springs 68 to reposition 'the balls 66 of the clutch assembly in locking position, at the same time causing the releasing ring 90 to be rotated `in the reverse direction with relation to the clutch assembly and dial to an intermediate neutral position so that the dial is securely held in the adjusted position.

While double acting ball clutches have been shown it will be understood that other double wedging type clutches may be employed, and rollers, for example, may b'e substituted for vthe balls in .the double clutch assembly within the spirit and scope of the invention.

The invention having been described what is claimed 1. For use in a machine tool having 'a shiftable part and a motion producing train for said part including a rotatable element in said train, an adjustable dial mechanism comprising a stationary indicator mounted on the machine, and a rotatable dial member cooperating with the indicator and freely rotatably with relation to said rotatable element, a double wedging type clutch normally connecting the rotatable dial lmember to turn with the rotatable element including a driving clutch element secured to 'said rotatable member having an internal cylindrical surface, a cooperating cam member connected with said dial member having peripherally disposed clutching surfaces including a low centrally disposed clutch disengaged ysurface and adjacent clutch surfaces oppositely inclined from said central low clutch disengaged surface, wedging devices interposed between said clutching surfaces and said internal cylindrical surface, yieldably acting means supporting said wedging devices in clutching relation between said inclined cam surfaces and overlying internal cylindrical surface, and a dial member releasing ring connected to the dial member having limited movement relative thereto, said dial member releasing ring having formed thereon arcuate projections projecting through said dial member arranged during said limited movement relative to the dial member to engage with and move at least one of said wedging members against said yieldably acting means to release the clutch, said dial member releasing ring being further movable thereafter with said dial member to effect movement of the dial member relative to said rotatable element.

2. An adjustable micrometer dial mechanism adapted for association with a shaft forming part of the feed mechanism of a movable machine element which comprises a stationary indicator, and a cooperating dial member freely rotatable on said shaft, a wedge type clutch connecting the dial member with the shaft comprising a cam ring having peripherally disposed clutching surfaces including a low centrally disposed clutch disengaged surface and adjacent oppositely inclined camsurfaces connected to turn with said dial member, and a wedging element retaining housing having an internal peripheral surface overlying said cam ring and connected to turn with the shaft, spring pressed wedging clutch elements interposed between the inclined cam surfaces of said cam ring and said peripheral surface of the wedging element retaining housing normally locking said cam ring and wedging element retaining housing to turn as a unit, and a releasing ring connected with said dial member for a limited rotational movement relative thereto, said releasing ring having formed thereon arcuate projections projecting through said dial member arranged upon said limited rotation of said ring in either direction to engage and release said clutch wedging elements, the further rotational movement of said releasing ring acting thereafter to rotate said dial member relative to said shaft for effecting an angular adjustment of micrometer fineness between said shaft and said dial member.

3. An adjustable micrometer dial mechanism adapted for association with a rotatable shaft forming part of the feed mechanism of a movable machine element,

which comprises a stationary indicator, a cooperating dial member freely rotatable on said shaft, a wedge type clutch interposed between said shaft of said feed mechanism and said dial member comprising a driving clutch element connected to be rotated by said shaft of said feed mechanism, a driven clutch element connected to turn with said dial, said latter clutch element having a plurality of opposed oppositely inclined clutch surfaces, a plurality of pairs of wedging elements arranged to be engaged between said respective oppositely inclined clutch surfaces, spring means normally forcing said wedging elements against the respective inclined surfaces, and a manually operable releasing ring keyed to turn as a unit with said dial member for effecting an angular adjustment of micrometer iineness between said shaft and said dial member and having a limited axial movement with relation to said dial member between retracted and release positions, said releasing ring having formed thereon arcuate segments projecting through said dial member and having beveled surfaces disposed by axial movement of said releasing ring to said release position to engage against and simultaneously shift each of said wedging elements away from the respective inclined surfaces, and yieldable means acting against said releasing ring to support said releasing ring normally in said retracted position.

References Cited in the file of this patent UNITED STATES PATENTS 2,202,217 Mallory May 28, 1940 2,319,480 Saving et al. May 18, 1943 2,633,213 Houplain Mar. 3l, 1953 2,743,699 Hollis May 1, 1956 2,777,417 Domin Ian. 15, 1957 2,787,353 Spraragen Apr. 2, 1957 FOREIGN PATENTS 346,278 Italy Feb. 5, 1937 

